The present invention is directed to a multi-edged cutting mechanism for use with strapping tools. More particularly, the present invention pertains to a multi-edged cutting mechanism having cutting surfaces defining elongate cutting edges, retaining surfaces, and a movable die holder with a slot defining tabs having a support surface for the cutting body.
It is desirable to provide multi-edged cutters for, portable or hand-held strapping tools so that when one cutting edge wears out, a replacement is immediately available. Examples of multi-edge cutters include the triple edged cutters of U.S. Pat. Nos. 5,499,664 and 5,848,621.
Typically, cutters provide a single cutting edge, which moves up and down with the motion of a holder. One such strapping tool, commercially available from ITW SIGNODE CORPORATION of Glenview, Ill., attaches a single-edged cutter to a die holder with a pin. On the downstroke, i.e., the cutting stroke, a cutter support surface on the die holder forces the cutting edge through a strap. On the up stroke, the attaching pin pulls the cutter back up.
Cutters that provide multiple cutting edges, such as the cutters described in the above-cited patents, frequently require separate cutting holders and include return springs to return the cutter during the upstroke. In addition to unnecessarily complicating cutter function, the more parts that are required, the greater the opportunity for malfunction or breakage.
Accordingly, there exists a need for a multi-edged cutting mechanism that provides a simple means of connecting the cutting surfaces and edges to the rest of the cutting mechanism. Such a cutting mechanism reduces the number of parts and conveniently provides at least one immediately available replacement cutter. It also protects the cutting edges not in use from any damage.